Bus factor: co-maintainer onboarding + handoff docs

[whisper67265]

Close #159.

Summary by CodeRabbit

• Documentation

  • Added CONTRIBUTING.md, MAINTAINERS.md, and docs/maintainer-handoff.md with clearer setup, testing, governance, and maintainer onboarding guidance.
  • Updated the README to surface governance links and simplified the contributing section to point to the new guides.

• Chores

  • Added structured GitHub issue templates for bug reports and feature requests, including guided form fields.
  • Added CODEOWNERS and updated packaging metadata so these new documents are included in source distributions.

[coderabbitai]

No actionable comments were generated in the recent review. 🎉

ℹ️ Recent review info

⚙️ Run configuration

Configuration used: defaults

Review profile: CHILL

Plan: Pro

Run ID: 9073c62b-ef7c-4e57-91e9-1e8be84c5fe3

📥 Commits

Reviewing files that changed from the base of the PR and between 8cd0249 and 09d4c01.

📒 Files selected for processing (1)

• docs/maintainer-handoff.md

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📝 Walkthrough

Walkthrough

Adds governance and contributor documentation, GitHub issue templates, maintainer handoff guidance, and README/packaging links for the new docs set.

Changes

Governance and contributor documentation

Layer / File(s)	Summary
CODEOWNERS and GitHub issue templates .github/CODEOWNERS, .github/ISSUE_TEMPLATE/bug_report.yml, .github/ISSUE_TEMPLATE/feature_request.yml, .github/ISSUE_TEMPLATE/config.yml	Adds code ownership assignment and structured issue forms for bug reports and feature requests, plus issue template config disabling blank issues and adding contact links.
Contributor guide CONTRIBUTING.md	Adds the contributor guide covering setup, hooks, testing, Weblate integration testing, version pin workflow, benchmark workflow, PR expectations, and reference links.
Maintainer roster MAINTAINERS.md	Adds maintainer identities, contact info, escalation steps, community channels, Discussions setup guidance, and related documentation links.
Maintainer handoff technical doc docs/maintainer-handoff.md	Adds Weblate coupling-point documentation and the first verified change walkthrough.
README and packaging updates README.md, pyproject.toml	Adds governance links and reference table entries, shortens the contributing section, and updates source-include to package the new docs.

Estimated code review effort: 2 (Simple) | ~12 minutes

Possibly related PRs

• cppalliance/cppa-weblate-plugin#108: Both PRs update pyproject.toml's tool.uv.build-backend.source-include to add markdown files to the sdist and adjust README.md documentation links.

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Description Check	✅ Passed	Check skipped - CodeRabbit’s high-level summary is enabled.
Title check	✅ Passed	The title clearly summarizes the main change: co-maintainer onboarding and handoff documentation.
Linked Issues check	✅ Passed	The changes satisfy #159 by adding maintainer roles, contributor and handoff docs, issue templates, and CODEOWNERS as requested.
Out of Scope Changes check	✅ Passed	The README and pyproject updates are directly tied to the onboarding and packaging changes, so no clear out-of-scope work stands out.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.

✨ Finishing Touches

🧪 Generate unit tests (beta)

• Create PR with unit tests

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_{Comment @coderabbitai help to get the list of available commands.}

[henry0816191]

This pr does not reflect the PR 162 that has already merged. Please rebase on develop branch and then update maintainer-handoff.md